An indepth look at weather and climate by South Carolina's Weatherman Jim Gandy.

Tuesday, January 7, 2014

Weather? Climate? Confused?

Have
you noticed the attention the weather has been getting in the media?The cold blast for much of the U.S. &
Canada, the trapped ship in the Antarctic, and the storms hitting Europe around
Christmas are just a few examples.Other
news reports that you may not have been aware were the floods in southern
Brazil and in the Caribbean, the heat wave in Argentina, the usually cold
weather in the Middle East.These are
all weather events.

Some
media outlets are reporting the cold events indicate that we have little to
fear from global warming.Yet global
warming does not cancel the seasons.In
fact what we know about our changing climate is to expect more weather extremes
worldwide.Not just heat waves, but
more floods, droughts, and even energized storm systems.This is how a changing climate translates into
daily weather.

Often
many in the media confuse the difference between weather and climate.Don’t worry, because some meteorologists do
too.The weather is basically composed
the events that unfold in the present.Meanwhile climate looks at the long term average of weather.By definition this is a 30-year period.We can look at shorter term trends to look at
how changes are progressing, but we still have to look at the climate period of
30 years.

There
has been much written about a pause in global warming however, all of these
claims cherry-pick the data to start at 1998 which was an unusually warm year
caused by a record El Nino.The blogger
Tamino at Open Mind has looked at the record statistically and has some good
post here and here.Stefan Rahmstorf at RealClimate.org
also has an excellent post on the surface temperature record.

Global surface temperatures since 1970 with the trend line. The trend has been a warming of 0.17°C/decade. The year 1998 was extremely warm due to El Nino. Click on image for a larger view. Image Credit: Dr. Marshall Shepherd.

Each
year the global temperature is affected by natural and man-made components of
the environment.The natural components
include insolation (incoming solar radiation), volcanic activity, the planetary
orbital cycles, and oceanic cycles.The
man-made component includes the burning of fossil fuels, deforestation, and
aerosols (like soot).These change every
year and help create the variability we see over the long-term.

Global
warming is a climatic event while the cold temperatures we are experiencing are
a weather event.The cold weather is
real and global warming is real.In
fact, the preliminary information indicates that 2013 was the 4th
warmest year on record.

The temperature anomaly for the lower troposphere in 2013. Preliminary information is that it was the 4th warmest on record for the satellite era. Click on the image for a larger view. Image Credit: nsstc.uah.edu.

Is
there a connection between climate change and the cold weather we are
experiencing?

There
could be.Recent studies indicate that
the warming Arctic is leading to a phenomenon known as warm arctic/ cold continents.A paper was just published indicating
that the phenomenon is becoming more common.We saw a similar event in December,
2010.

Bottomline:
Cold outbreaks are not new.What is news
is that this is the coldest in recent memory which is why we have records.Weather events occur in the context of
climate, but single events do not determine climate.As Dr. Marshall Shepherd is fond of saying “weather
is your mood, climate is your personality”.Your mood changes for day-to-day, but your personality lasts a long
time.

About Me

A professional meteorologist for over 37 years, Jim Gandy is the chief meteorologist at WLTX-TV (CBS affiliate) in Columbia, SC. He has held that position since 1999.
Jim is a Certified Broadcast Meteorologist and has a number of awards and recognitions for his work over the years. He is best known for his forecast of Hurricane Hugo in 1989 and his work during the tornado outbreak in South Carolina in 1994.
Jim continues to study weather and is interested in climate change which he has studied since 2005. Looking for better ways to communicate climate change, he is working with the Center for Climate Change Communication at George Mason University and with Climate Central.
Jim recently began working with the Helmuth Lab at the University of South Carolina. Dr. Brian Helmuth is working in the area of the effects of climate change on the ecology.
All of these subjects are of vital interest to South Carolina.